On 07/09/2016 21:48, pedro wrote:
Have a gas wall oven with two supply gas valves/solenoids in series -
safeguard against one sticking open, one presumes. Coils are
connected in parallel. These are situated on TOP of (doh!) the oven
shell - not the brightest move but placed there no doubt for service
access - tick.

Original coils were by Goyen Controls, and lasted 20 years before one
failed. By then Tyco had moved in (TYCO=TakeYourCompanyOver). Tyco
replacement lasted about 18 months,during which time the other Goyen
coil died. Ever since, the Tyco replacements (at ~$A70 each) have
lasted about 18 months.

It transpires that about the time I got the first Tyco coils, they had
transitioned the Oz factory to ROHS. Now these coils are 240VAC so
the winding wire is as fine as all getout. How is it terminated? Ah,
it is SOLDERED to 1/4" QC/Faston terminals which protrude out through
the epoxy/"thermoplastic" former. Evidently thermal cycling is
causing solder joint failures, but the necessary surgery with a Dremel
to reach the joint would - apart from compromising the overall
integrity and insulation characteristics - probably take out untold
turns of the coil itself, rendering the operation pointless.


Can you buy the same coil type but in a 24 Volts AC version? If so, that
plus a transformer may be more reliable than the 240VAC version.